Fifteen years ago a landmark study of drug use among arrestees was done in six cities across the U.S. The study used both self-report and urine analyses to establish drug use patterns. Since the earlier study, drug use patterns have changed markedly, alcohol use has been more strongly linked to criminal behavior, and the substance use-criminal behavior relationship has changed--especially as regards violent crime. Because of the changes, a new study is proposed to replicate and extend the earlier study. The new study has three major aims: (1) using multiple indicators of drug use, determine the nature and extent of drug use and criminal behavior among arrestees in 1986, and compare the findings to those from 1971; (2) analyze the relationship of specific drugs and multiple drug use combinations to types of arrest charges, and compare these patterns for 1986 and 1971; and (3) compare criminal justice process outcomes and arrestee behavior during a 12-month follow-up period for drug users and nonusers. Diversion to drug abuse treatment will be a special focus of aim number three. The study will be done in three urban areas and will utilize data from interviews, urine analyses, and criminal justice records for approximately 1950 new arrestees. Additional goals of the research will be comparison of drug use findings from self-report and urine analyses to assess bias in the self-report data, and comparison of self-reports of arrest to official records of arrest to assess the accuracy of self-reports of arrest. Finally, career analyses of drug use and criminal behavior will focus on how these activities vary over time. The study will be of historical interest by providing a comparison of drug use patterns among arrestees in 1971 and 1986. The research will also provide a detailed picture of contemporary drug-crime relationships and may suggest how criminal justice and drug abuse treatment decisionmakers can collaborate effectively to deal with drug abusing offenders.